女性的正常月经持续时间为2至7天,少数是3至5天。如果月经持续时间超过7天,就属于经期延长。经期延长通常与以下的疾病有关: (1)血液病:如血小板减少性紫癫、再生障碍性贫血等,月经来潮时,如果出现严重的子宫出血,经期就会延长。其他如慢性贫血、慢性肝炎、肝硬化、肾炎等,也会让血管壁脆弱,通透性增加而造成出血。(2)盆腔炎症、子宫 Normal menstruation in women lasts from 2 to 7 days, with a few from 3 to 5 days. If the duration of menstruation more than 7 days, it belongs to the menstrual extension. Menstrual delay usually associated with the following diseases: (1) blood diseases: such as thrombocytopenic purpura, aplastic anemia, menstrual cramps, if there is a serious uterine bleeding, menstrual period will be extended. Others such as chronic anemia, chronic hepatitis, cirrhosis, nephritis, etc., also make the vessel wall fragile, increased permeability caused by bleeding. (2) pelvic inflammatory disease, the uterus